1. Field of the Invention:
This invention relates generally to multiple animal feeders, and more specifically to a compact self-limiting feeder suitable for space saving installation along the side or between animal pens.
2. Description of the prior art:
Animals are commonly raised through most or all of their life in pens. This is particularly true of pigs. Groups of animals of a common size or age or of particular ancestry are kept together in individual holding and feeding pens. The pens along with abutting or adjacent pens are usually enclosed in a confinement building in order to control the environment. The economics require that the number of animals in a given amount of space in each pen be maximized.
Nevertheless, each feeding operation establishes a maximum number of animals in a unit of space or in a pen of a given size because overcrowding becomes counterproductive for a variety of reasons and can lead to sickness, unhealthy animals and reduced feeding efficiency. Therefore use of the available square foot floor surface area is at a premium for an efficient feeding operation. A compact feeding apparatus is desirable to avoid excessive use of the available floor space.
In addition to the space consideration it is important in a modern animal feeding operation to reach market weight with the minimum total consumption of feed. Feed is probably the most expensive single element of cost in a market feeding operation. Therefore it is important to obtain maximum feeding efficiency and to avoid wastage or spoilage of feed. Many animal feed pens, particularly for pigs, do not have solid floors but rather have grates or slats which permit animal waste to be conveniently removed from the enclosure. Therefore in such systems it is important to avoid spillage of feed on the floor of the pen because it simply passes through the floor along with the waste and is lost.
Additionally many operators believe that the overall feeding efficiency is improved if the feed is not allowed to become stale by exposure to the animal environment which causes feed to become contaminated with barn odors by such exposure over a period of time and can lead to spoilage. Spoiled feed can also create health problems in the feeding pigs.
A typical animal feeder is built in the shape of the letter "L" when viewed from the end. The upright section constitutes a hopper which holds a large quantity of feed. The hopper is mounted on a base which has a large flat area that extends out horizontally on one or both sides to provide room for a number of feeding stations. A manually operated gate can be raised or lowered and fixed in position between the hopper portion of the feeder and the horizontally extended base. Raising the gate to an intermediate position above the bottom of the base provides a gap through which feed can come down from the hopper and outwardly under the gate into the extended portion of the base for access to the feeding stations. A wire loop agitator for each feeding station extends from the hopper under the gate into each horizontally extending feeding station. The agitator is intended to facilitate flow of fresh feed by mechanical agitation caused by the feeding movements of the animals.
Other conventional feeders of a similar nature are round having a central feed storage compartment with multiple feed stations around the circumference of an extended lower flat bottomed base. This configuration necessitates placement of the feeder in the center of the pen in order to provide access for multiple animal feeding. Both of the feeders just described require large base areas for stability which tends to reduce the number of animals which can be fed in a given pen size.
The conventional feeders also have a fairly large open area at each feeding station which, particularly in the case of rooting animals like pigs, allows the feed to be thrown out onto the floor area during feeding which causes loss. The flat floor area of the base of the typical feeders has inaccessible corners which accumulate feed that spoils fast particularly where moisture is present.
Moisture from the mouth and nose of the feeding animals also clogs the feeder gates and eventually in spite of the wire loop agitators causes bridging of feed and provides an insufficient supply of food which necessitates frequent cleaning and readjustment in order to reestablish satisfactory feeding conditions. This situation aggravates the problems of feed spoilage and wastage and pick up of barn odors because the natural tendency of the operators is to use a higher gate setting in order to avoid the clogging with the result that an excessive amount of feed is allowed to pass into and be held in the feeding station areas.